Product Description:

The MRS312D-1N-0170-NNNN is a rotor-equipped synchronous motor supplied by Bosch Rexroth Indramat within the MRS Synchronous IndraDyn H Motors series. In an automation cell, this part converts electrical excitation from the stator into mechanical torque. Its multi-pole rotor layout supports accurate position control for indexing tables and direct-drive spindles, and it is suited to applications that need smooth rotary motion at controlled speed.

The rotor’s internal diameter measures 170 mm, and its outside diameter extends to 238 mm; these dimensions set the radial air gap that influences magnetic flux. An overall stack length of 494 mm sets the axial magnetic path and supports continuous torque output across the active length of the rotor. The assembly weighs 67.4 kg, and its rotational mass distribution produces a moment of inertia of 0.751 kgm², which affects acceleration response when the drive applies torque. The magnetic circuit uses 7 pole pairs, so one electrical cycle turns the shaft 51.43° and allows the controller to command fine angular increments. These values affect acceleration, servo tuning, and the operating speed range under load.

The rim carries 24 x M8 x 12 mm deep balancing holes so mass can be added or removed to minimize residual vibration. A bore tolerance of H6 provides a close fit on the machine shaft, while a 30° mounting chamfer guides the rotor over keys or splines without scoring the bore. The close fit helps transmit torque without unwanted play at the hub interface. The bore uses smooth drilling to maintain concentricity, and the mounting face is finished to Rz16 to help preserve bearing alignment. An undercut no wider than 5 mm reduces stress concentration near the hub during cyclic torsion in continuous duty.